Membrane electrode transfer printing assembly

Abstract

The utility model provides a transfer printing assembly of a membrane electrode, which comprises a transfer printing plate, a first transfer printing plate and a second transfer printing plate, the first transfer printing plate and the second transfer printing plate are respectively provided with an opening to determine a transfer printing area, the first transfer printing plate and the second transfer printing plate are further provided with positioning holes, and the positioning holes are used for positioning the first transfer printing plate and the second transfer printing plate. The positions of the positioning holes in the first transfer printing plate and the second transfer printing plate are the same; and a positioning member. According to the transfer printing assembly of the membrane electrode, the defect that large-area bubbles are generated in a catalyst area after transfer printing can be avoided, and the quality of the membrane electrode is improved.

Description

[0001] This application is a divisional application. The application number of the original application is 202421471546.0, and the filing date of the original application is June 26, 2024. The entire content of the original application is incorporated herein by reference. Technical Field

[0002] The utility model relates to the technical field of hydrogen production by electrolyzing water, and particularly to a transfer assembly for a membrane electrode. Background Art

[0003] As the core component of the water electrolysis hydrogen production technology, the membrane electrode is composed of an electrode catalyst layer, an electrode catalyst layer and a membrane layer, which play roles such as conducting protons, catalyzing reactions and separating gases, and determine the performance, efficiency, lifespan and cost of water electrolysis hydrogen production.

[0004] However, in the membrane electrode, the electrode catalyst layer and the membrane layer are prone to peeling, and the stability of the membrane electrode is poor. At the same time, during the electrolysis process, hydrogen can permeate through the membrane layer from the cathode to the anode, and the mixing of hydrogen and oxygen will reduce the performance of the membrane electrode, and in severe cases, it will cause an explosion, with prominent safety problems. Summary of the Utility Model

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the utility model is to provide a transfer assembly for a membrane electrode, and the utility model is realized through the following technical solutions.

[0006] The utility model provides a transfer assembly for a membrane electrode, comprising:

[0007] A transfer plate, including a first transfer plate and a second transfer plate. The first transfer plate and the second transfer plate are respectively provided with openings to determine the transfer area. The first transfer plate and the second transfer plate are also provided with positioning holes, and the positions of the positioning holes on the first transfer plate and the second transfer plate are the same;

[0008] A positioning member;

[0009] Wherein, during the transfer, the membrane layer of the membrane electrode is placed between the first transfer plate and the second transfer plate, and the positioning member is placed in the positioning hole to fix and position the membrane layer of the membrane electrode.

[0010] In an embodiment of the utility model, the positioning holes are arranged at the diagonal positions of the first transfer plate and the second transfer plate.

[0011] In an embodiment of the utility model, the positioning member is a fluorine-containing rubber member.

[0012] In an embodiment of the present utility model, the first transfer plate and the second transfer plate are of the same size, and openings with the same size and position are respectively provided at the centers of the first transfer plate and the second transfer plate to determine the transfer area.

[0013] In an embodiment of the present utility model, the transfer assembly of the membrane electrode further includes a first transfer film and a second transfer film. During transfer, the first transfer film is disposed on the side of the first transfer plate away from the membrane layer, and the slurry layer on the first transfer film faces the membrane layer. The second transfer film is disposed on the side of the second transfer plate away from the membrane layer, and the slurry layer on the second transfer film faces the membrane layer.

[0014] In summary, the present utility model can determine the transfer area, ensure that the areas of the regions where the catalytic layers are located on both sides of the membrane layer are the same after transfer, and the regions where the catalytic layers are located are aligned. Air during the transfer process or water vapor generated by heating can be discharged from the edges of the openings. In this application, the size of the openings is not limited and can be set according to the size of the membrane electrode to meet the preparation requirements for forming a larger membrane electrode.

[0015] Of course, not necessarily all of the above advantages need to be achieved simultaneously when implementing any aspect of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic flow chart of the preparation method of the membrane electrode in an embodiment of the present utility model.

[0018] Figure 2 It is a physical diagram of the membrane electrode in an embodiment of the present utility model.

[0019] Figure 3 For Figure 2 the cross-sectional view of the microscopic morphology of the membrane electrode.

[0020] Figure 4 For Figure 3 the enlarged view of the membrane layer and the electrode catalyst layer.

[0021] Figure 5 For Figure 2 the stability curve diagram of the membrane electrode.

[0022] Figure 6 It is a schematic diagram of the membrane layer and the electrode catalyst layer in an embodiment of the present utility model.

[0023] Figure 7 This is a micrograph of the film layer and the electrode catalyst layer in an embodiment of the present utility model.

[0024] Figure 8 This is a schematic structural diagram of a membrane electrode in an embodiment of the present utility model.

[0025] Figure 9 This is a schematic diagram of the distribution of the hydrogen consumption layer on the film layer in an embodiment of the present utility model.

[0026] Figure 10 This is a schematic diagram of the flow channel in the cathode catalyst layer in an embodiment of the present utility model.

[0027] Figure 11 This is a schematic diagram of the distribution of the hydrogen consumption layer on the film layer in another embodiment of the present utility model.

[0028] Figure 12 This is a schematic structural diagram of a membrane electrode during transfer printing in an embodiment of the present utility model.

[0029] Figure 13 This is a scanning electron micrograph of an electrode catalyst layer obtained by the transfer printing method of the present utility model in an embodiment.

[0030] Figure 14 This is a scanning electron micrograph of a conventionally obtained electrode catalyst layer. Detailed implementation manners

[0031] The following uses specific specific examples to illustrate the implementation manners of the present utility model. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0032] It should be understood that the present utility model can be implemented in different forms and should not be construed as limited to the embodiments presented here. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present utility model to those skilled in the art.

[0033] The technical solutions of the present utility model will be further described in detail below in conjunction with the embodiments and the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0034] Please refer to Figure 1 As shown, the present utility model provides a method for preparing a membrane electrode, which at least includes steps S11 - S15.

[0035] S11. Provide a membrane layer, the membrane layer including a first surface and a second surface which are oppositely arranged.

[0036] S12. Coat the precursor solution on the first surface.

[0037] S13. Coat the adhesion enhancer on the precursor solution.

[0038] S14. Place the membrane layer in an alkaline solution for growth to in-situ grow an electrode catalyst layer on the first surface.

[0039] S15. Repeat the above steps for the second surface using the precursor solution, the adhesion enhancer, and the alkaline solution to in-situ grow another electrode catalyst layer on the second surface to obtain the membrane electrode.

[0040] Please refer to Figure 1 As shown, in an embodiment of the present utility model, in step S11, the membrane layer 100 is, for example, a diaphragm, a cation exchange membrane, an anion exchange membrane, a proton exchange membrane, a porous membrane, or other membrane layers that can be used for hydrogen production electrolysis. The membrane layer 100, for example, includes a first surface and a second surface which are oppositely arranged. Further, before use, the membrane layer 100 needs to be pretreated to remove impurities on the first surface and the second surface so that the membrane layer 100 can be closely attached to the subsequently formed electrode catalyst layer 200 and electrode catalyst layer 300. In an embodiment of the present utility model, the pretreatment, for example, includes soaking the membrane layer 100 in a solvent at a preset temperature for a preset time, then taking out the membrane layer 100 and rinsing it with deionized water, and then putting it into an oven for drying. Among them, the solvent is, for example, at least one of hydrogen peroxide and sulfuric acid, etc., the preset temperature is, for example, 50°C - 90°C, and the preset time is, for example, 0.5h - 5h.

[0041] Please refer to Figure 1As shown, in an embodiment of the present utility model, after providing the film layer 100, before coating the precursor solution in step S12, the precursor solution also needs to be homogenized to obtain a uniform precursor solution. Among them, the method of homogenization treatment, for example, includes ultrasonic stirring treatment of the precursor solution, and the ultrasonic stirring time is, for example, 1 min - 2 h. In this embodiment, the precursor solution, for example, includes a metal compound and a solution. Among them, the metal compound is, for example, selected from at least two of transition metal compounds, rare earth metal compounds, and noble metal compounds. The transition metal compound, for example, includes metal compounds such as manganese, chromium, iron, cobalt, nickel, copper, zinc, molybdenum, or tungsten. The rare earth metal compound, for example, includes lanthanide rare earth metal compounds, etc. The noble metal compound, for example, includes platinum group noble metal compounds, etc. In this embodiment, the metal compound is, for example, a metal salt or a metal halide, etc. The metal salt is, for example, a metal sulfate, a metal nitrate, or a metal chromate, etc. The solvent, for example, includes at least one of alcohol solvents such as ethanol, ethylene glycol, propanol, and isopropyl alcohol, etc.

[0042] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after homogenizing the precursor solution, in step S12, the precursor solution is coated on the first surface. Among them, the method of coating the precursor solution on the first surface, for example, adopts any one of immersion or ultrasonic spraying, etc. Specifically, when the immersion method is adopted, first, glue is coated on the second surface, and the second surface is dried to form a protective layer on the second surface. Then, the film layer 100 with the protective layer is immersed in the precursor solution. Among them, the glue, for example, includes at least one of epoxy resin, acrylic modified epoxy resin, and perfluorosulfonic acid resin, etc. By coating glue on the second surface to form a protective layer, it can be avoided that the precursor solution adheres to the second surface, so that the electrode catalyst layer 200 can be accurately formed on the first surface.

[0043] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after coating the precursor solution on the first surface, in step S13, a binding force enhancer is coated on the precursor solution. Among them, the binding force enhancer is, for example, selected from at least one of potassium borohydride, sodium borohydride, glucose, methanol, diisobutylaluminum hydride, ascorbic acid, hydrazine, and sodium sulfite, etc. The method of coating the binding force enhancer on the precursor solution, for example, includes any one of immersion or ultrasonic spraying, etc. When, for example, the immersion method is adopted in step S12 to coat the precursor solution on the first surface, in step S13, the binding force enhancer can be added to the precursor solution, and the film layer 100 is continuously immersed in the precursor solution containing the binding force enhancer.

[0044] Please refer to Figure 1As shown, in an embodiment of the present utility model, after applying a bonding strength enhancer on the precursor solution, in step S14, the film layer 100 with the bonding strength enhancer and the precursor solution is immersed in an alkaline solution for growth. Among them, the pH of the alkaline solution is, for example, 8 - 14, the alkaline solution is, for example, selected from at least one of alkaline solutions such as sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate, and potassium bicarbonate, the temperature of the alkaline solution is, for example, 30°C - 90°C, and the immersion time of the film layer 100 in the alkaline solution is, for example, 5 min - 1200 min.

[0045] Please refer to Figure 1 As shown, in an embodiment of the present utility model, during the process of immersing the film layer 100 in the alkaline solution in step S14, the precursor solution coated on the film layer 100 grows in situ on the first surface to form an electrode catalyst layer 200. Moreover, during the in-situ growth process, the bonding strength enhancer coated on the precursor solution can enhance the bonding strength between the electrode catalyst layer 200 and the film layer 100, enabling the electrode catalyst layer 200 and the film layer 100 to be closely attached, thereby improving the stability of the membrane electrode.

[0046] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after completing step S14, that is, after the immersion of the film layer 100 in the alkaline solution is completed, the film layer 100 needs to be taken out from the alkaline solution and the film layer 100 is rinsed to remove the alkaline solution adhering to the first surface. Among them, the solvent for rinsing the film layer 100 includes, for example, at least one of deionized water and alcohol reagents, etc. Further, when steps S12 and S13 use the immersion method to coat the precursor solution and the bonding strength enhancer on the first surface, before rinsing the film layer 100, the protective layer on the second surface also needs to be removed.

[0047] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after rinsing the film layer 100, in step S15, the precursor solution, the bonding strength enhancer, and the alkaline solution are used to repeat steps S12 - S14 on the second surface to in-situ grow an electrode catalyst layer 300 on the second surface. Specifically, the precursor solution is coated on the second surface, then after applying the bonding strength enhancer on the precursor solution, the film layer 100 is placed in the alkaline solution for growth. After the growth is completed, the film layer 100 is taken out from the alkaline solution and the film layer 100 is rinsed. Among them, compared with the formation process of the electrode catalyst layer 200, the difference in the formation process of the electrode catalyst layer 300 is that in the precursor solution, the transition metal compound includes, for example, metal compounds such as manganese, chromium, iron, cobalt, nickel, copper, or zinc, and the rest are exactly the same, and will not be elaborated here.

[0048] Please refer to Figure 1As shown, in an embodiment of the present invention, after forming the electrode catalyst layer 300 on the second surface and rinsing the membrane layer 100, the membrane layer 100 also needs to be dried to obtain a membrane electrode. Among them, the membrane layer 100 is dried by vacuum drying, for example, and the temperature for vacuum drying the membrane layer 100 is, for example, 50°C - 150°C. In the preparation method provided by the present invention, in an alkaline solution, the precursor solution and the precursor solution are respectively in-situ grown on the first surface and the second surface of the membrane layer 100 to form the electrode catalyst layer 200 on the first surface of the membrane layer 100 and the electrode catalyst layer 300 on the second surface of the membrane layer 100. Moreover, during the in-situ growth process, the binder enhancer on the precursor solution and the precursor solution can enhance the binding force between the electrode catalyst layer 200 and the first surface, as well as the binding force between the electrode catalyst layer 300 and the second surface, so as to improve the quality and stability of the membrane electrode. Moreover, the preparation method provided by the present invention can simplify the preparation process of the membrane electrode, reduce the preparation cycle and cost, and is suitable for large-scale production of the membrane electrode.

[0049] Please refer to Figure 1 As shown, the present invention also provides a membrane electrode obtained by the above-mentioned preparation method of the membrane electrode. The membrane electrode includes, for example, a membrane layer 100, an electrode catalyst layer 200, an electrode catalyst layer 300, etc. Among them, the membrane layer 100 includes a first surface and a second surface arranged opposite to each other. The electrode catalyst layer 200 is, for example, disposed on the first surface, and the electrode catalyst layer 300 is, for example, disposed on the second surface. In the membrane electrode provided by the present invention, in an alkaline solution, the precursor solution is in-situ grown on the first surface or the second surface to form the electrode catalyst layer 200 or the electrode catalyst layer 300. Moreover, during the in-situ growth process, the binder enhancer can enhance the binding force between the electrode catalyst layer 200 and the first surface, as well as the binding force between the electrode catalyst layer 300 and the second surface, so that the membrane layer 100 and the electrode catalyst layer are tightly combined, and the electrode catalyst layer and the membrane layer 100 are not easily peeled off, thereby improving the stability of the membrane electrode and the utilization rate of the catalyst in the electrode catalyst layer, and improving the efficiency of hydrogen production by water electrolysis.

[0050] Please refer to Figures 1 to 2 As shown, in an embodiment of the present invention, a membrane electrode is obtained according to the preparation method of the membrane electrode, and the physical diagram of the membrane electrode is as Figure 2 shown.

[0051] Please refer to Figures 3 to 4 As shown, in an embodiment of the present invention, for Figure 2 the membrane electrode in is characterized, for example, by scanning electron microscopy to characterize the cross-section of the membrane electrode and magnify the area between the electrode catalyst layer 200 and the membrane layer 100. Among them, Figure 3 the magnification of is, for example, 100 times, Figure 4The magnification factor is, for example, 400 times. Combining Figure 3 and Figure 4 it can be seen that in the membrane electrode, the electrode catalyst layer 300 and the electrode catalyst layer 200 are respectively located on both sides of the membrane layer 100. Moreover, there is a fusion region 201 between the electrode catalyst layer 200 and the membrane layer 100. In the fusion region 201, the electrode catalyst layer 200 grows on the membrane layer 100 and diffuses in the direction where the membrane layer 100 is located. At this time, part of the electrode catalyst layer 200 can be embedded or fused into the membrane layer 100. The membrane layer 100 and the electrode catalyst layer 200 are tightly combined and have better binding stability. In some embodiments, the depth of the electrode catalyst layer 200 embedded in the membrane layer 100 is, for example, 10 nm to 7 μm.

[0052] It should be noted that by the method of the present application, the electrode catalyst layers 200 can be directly grown on the opposite sides of the membrane layer 100 respectively to form the membrane electrode of the electrolytic cell. However, it is not limited thereto. In some embodiments, by the method of the present application, the electrode catalyst layer 200 can also be grown only on one side of the membrane layer 100. On the other side of the membrane layer 100, the electrode catalyst can be formed on the diffusion layer. That is, in the membrane electrode of the present application, the electrode catalyst layer 200 can be formed on one side or the opposite sides of the membrane layer 100. For example, in the AEM membrane electrode, the electrode catalyst layer 200 can be formed on one side of the membrane layer 100, and the other electrode catalyst layer 200 can be formed on the diffusion layer.

[0053] Please refer to Figure 5 as shown. In an embodiment of the present invention, the stability of the Figure 2 membrane electrode is characterized. Specifically, the membrane electrode is loaded to a preset current density, and the change of the membrane electrode voltage within 100 h is measured. Among them, the preset current density is, for example, 2 A / cm 2 . From Figure 5 it can be seen that within 0 - 70 h, the voltage of the membrane electrode fluctuates stably around 1.94 V and tends to 1.94 V. Therefore, the stability of the membrane electrode is relatively good.

[0054] Please refer to Figure 6 and Figure 7As shown, in an embodiment of the present utility model, on the anode side of the membrane layer 100, the electrode catalyst layer 300 may include a first metal catalyst layer 301 and a second metal catalyst layer 302. The first metal catalyst layer 301 is formed on the membrane layer 100 and may partially penetrate or embed into the membrane layer 100. The second metal catalyst layer 302 is formed on the first metal catalyst layer 301. The first metal catalyst layer 301 and the second metal catalyst layer 302 may have different metal catalysts. For example, the first metal catalyst layer 301 may include a platinum metal catalyst, and the second metal catalyst layer 302 may include an iridium or iridium oxide metal catalyst. By using different metal catalysts, the usage load of noble metal (such as iridium) catalysts can be reduced, thereby reducing costs.

[0055] In an embodiment, the thickness of the first metal catalyst layer 301 is, for example, 5 nm to 200 nm, and the thickness of the second metal catalyst layer 302 is, for example, 50 nm to 5 μm.

[0056] In an embodiment, the nanoparticle size of the metal catalyst in the first metal catalyst layer 301 is, for example, 1 nm to 15 nm, and the nanoparticle size of the metal catalyst in the second metal catalyst layer 302 is, for example, 10 nm to 200 nm.

[0057] Please refer to Figure 8 As shown, in another embodiment of the present utility model, the membrane electrode provided by the present utility model includes a membrane layer 100, an anode catalyst layer 11, a cathode catalyst layer 12, etc. The anode catalyst layer 11 and the cathode catalyst layer 12 are respectively formed on both sides of the membrane layer 100. The anode catalyst layer 11 includes a hydrogen consumption layer 111 and an anode catalyst base layer 112. The hydrogen consumption layer 11 is formed between the membrane layer 100 and the anode catalyst base layer 113. By providing the hydrogen consumption layer 11, the hydrogen permeating from the cathode side to the anode can be eliminated in time, the purity of the gas can be improved, and the safety of the electrolytic water hydrogen production device can be improved.

[0058] Please refer to Figure 8 As shown, in an embodiment of the present utility model, the membrane layer 100 is, for example, an N115 proton membrane, etc., and the thickness of the membrane layer 100 is, for example, 110 μm to 130 μm, etc. The thickness of the N115 proton membrane is, for example, 127 μm to meet conduction, isolation, and thermal stability, etc.

[0059] Please refer to Figure 8As shown, in an embodiment of the present utility model, the hydrogen-consuming catalyst in the hydrogen-consuming layer 111 is, for example, selected from highly active and acid-resistant high-stability materials such as Pt, Ir, or Pd. The anode catalyst in the anode catalytic base layer 112 is, for example, a catalyst for catalyzing oxygen reactions, and is also, for example, selected from at least one of Ir, IrO₂, Pt, Pd, or Ru. Through the hydrogen-consuming catalyst in the hydrogen-consuming layer 11, the hydrogen-consuming catalyst in the hydrogen-consuming layer 11 can convert the hydrogen diffused from the cathode into hydrogen ions. A part of the oxygen generated on the anode side will diffuse into the hydrogen-consuming layer 111. The hydrogen-consuming catalyst in the hydrogen-consuming layer 111 can also convert the oxygen diffused into the hydrogen-consuming layer 11 into oxygen ions, enabling the hydrogen ions and oxygen ions to react to form water, so as to react hydrogen and oxygen to obtain water, thereby achieving the purpose of eliminating hydrogen on the anode side, improving the purity of oxygen on the anode side, and at the same time preventing oxygen from diffusing to the cathode, that is, it can improve the purity of both hydrogen and oxygen generated by electrolyzing water and enhance the safety of the electrolytic water device.

[0060] Please refer to Figure 8 As shown, in an embodiment of the present utility model, the cathode catalyst in the cathode catalytic layer 12 is, for example, a catalyst for catalyzing hydrogen reactions, and is also, for example, selected from at least one of Ir, IrO₂, Pt / C, Pt, Pd, or Ru.

[0061] Please refer to Figure 8 As shown, in an embodiment of the present utility model, the thickness ratio of the membrane layer 100, the anode catalytic layer 11, and the cathode catalytic layer 12 is, for example, 1:0.1:0.1 to 1:10:10, and is also, for example, 1:1.5:1.5, etc. And the thickness ratio of the hydrogen-consuming layer 111 and the anode catalytic base layer 112 is, for example, 1:1 to 1:10, 1:5, etc. In a specific embodiment of the present utility model, the total thickness of the membrane electrode is, for example, 154 μm. Within this thickness range of the membrane electrode and with the cooperation of the thicknesses of different layers, the electrolysis efficiency of the membrane electrode for water can be improved.

[0062] Please refer to Figure 8 As shown, in an embodiment of the present utility model, the porosity of the hydrogen-consuming layer 111 is, for example, 1 m 2 / g, the porosity of the anode catalytic base layer 112 is, for example, 100 - 330 m 2 / g, and the porosity of the cathode catalytic layer 12 is, for example, 100 - 330 m 2 / g. In a specific embodiment of the present utility model, the porosity of the hydrogen-consuming layer 111 is, for example, 130 m 2 / g, the porosity of the anode catalytic base layer 112 is, for example, 160 m 2 / g, and the porosity of the cathode catalytic layer 12 is, for example, 180 m 2 / g. Among them, the porosity of the anode catalyst layer 11 and the cathode catalyst layer 12 on both sides of the membrane layer 100 is relatively large, which can increase the number of pores in the membrane electrode, provide abundant pores for mass transfer, and thus improve the electrolysis rate.

[0063] Please refer to Figure 9 As shown, in an embodiment of the present invention, a schematic diagram of the distribution of the hydrogen consumption layer 111 on the membrane layer 100 is provided. During the electrolysis process, the hydrogen permeating through the membrane layer 100 gradually accumulates from the inlet to the outlet of the anode layer flow field. In some embodiments, the loading amount of the hydrogen consumption layer can be increased along the water flow direction of the anode catalyst layer. Therefore, on the anode side of the membrane layer 100, from the end of the membrane electrode far from the water flow direction to the end close to the water flow direction, the hydrogen consumption layer 111 on the membrane layer 100 increases, such as by increasing the width, loading amount, and density of the hydrogen-consuming catalyst of the hydrogen consumption layer 111. In Figure 9 part a, the hydrogen consumption layer 111 includes a plurality of arranged strip structures, and the width of the strip structures of the hydrogen consumption layer 111 increases sequentially towards the end close to the water flow direction. In Figure 9 part b, towards the end close to the water flow direction, the loading amount of the hydrogen consumption layer 111 increases sequentially, such as the thickness of the hydrogen consumption layer 111 increases. In Figure 9 part c, towards the end close to the water flow direction, the density of the hydrogen-consuming catalyst in the hydrogen consumption layer 111 increases sequentially. By setting different amounts of the hydrogen consumption layer 111 in different regions of the membrane layer 100, the removal efficiency of hydrogen on the anode side can be improved, while reducing the usage amount of the hydrogen-consuming catalyst and lowering the cost.

[0064] Please refer to Figure 10 and Figure 11 As shown, in another embodiment of the present invention, a schematic diagram of the distribution of the hydrogen consumption layer 111 on the membrane layer 100 is provided. The electrolytic cell includes a membrane electrode 10 and bipolar plates 20, and the bipolar plates 20 are respectively located outside the anode catalyst layer and the cathode catalyst layer of the membrane electrode. During the electrolysis process, due to the position of the cathode flow field ridge 201 of the plate 20 on the cathode catalyst layer side contacting the membrane layer 100, the membrane layer 100 at the contact part is under pressure, which is not conducive to hydrogen permeation, and the hydrogen content is low. The membrane layer 100 at the position of the flow channel 202 swells and has more microporous channels, which is conducive to hydrogen permeation. In some embodiments, the hydrogen consumption layer 111 can be provided with a bending structure (such as Figure 11 shown), and the bending structure of the hydrogen consumption layer 111 can be consistent with the flow field distribution of the plate outside the cathode catalyst layer. It can consume the hydrogen diffused from the flow channel 202, improve the removal efficiency of hydrogen on the anode side, and improve the safety of electrolysis.

[0065] In an embodiment of the present invention, the present invention also provides a preparation method of a membrane electrode, including steps S11 - S12.

[0066] Step S11: Form an anode catalyst layer on one side of the membrane layer. The anode catalyst layer includes a hydrogen consumption layer and an anode catalyst base layer, and the hydrogen consumption layer is formed between the membrane layer and the anode catalyst base layer.

[0067] Step S12: Form a cathode catalyst layer on the other side of the membrane layer.

[0068] In an embodiment of the present invention, the electrode catalyst layer (anode catalyst layer and / or cathode catalyst layer) can be formed, for example, by transfer printing. When performing transfer printing, the anode catalyst layer and the cathode catalyst layer can be transferred simultaneously or step by step. The hydrogen consumption layer and the anode catalyst base layer in the anode catalyst layer can be transferred simultaneously or step by step. When transferred synchronously, an anode catalyst base layer is formed on the transfer film, and after a hydrogen consumption layer is formed on the anode catalyst base layer, it is transferred onto the membrane layer. When transferred step by step, the hydrogen consumption layer is first transferred onto the membrane layer, and then the anode catalyst base layer is transferred onto the anode catalyst base layer. In this embodiment, for example, a non-vacuum hot press transfer printing method is used for transfer printing.

[0069] Please refer to Figure 12 As described, in an embodiment of the present invention, an anode catalyst paste layer and a hydrogen consumption paste layer are formed on the transfer film to form a first transfer film 15. Among them, the anode catalyst paste layer includes an anode catalyst and resin, etc. The anode catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the anode catalyst to the resin is, for example, 1:0.1 to 1:3. The anode catalyst paste layer is formed, for example, by doctor blading, roll coating, or spraying. The hydrogen consumption paste layer includes a hydrogen-consuming catalyst and resin, etc. The hydrogen-consuming catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the hydrogen-consuming catalyst to the resin is, for example, 1:0.5 to 1:3. The hydrogen consumption paste layer is formed, for example, by doctor blading, roll coating, or spraying.

[0070] Please refer to Figure 12 As described, in an embodiment of the present invention, a cathode catalyst paste layer is formed on the transfer film to form a second transfer film 16. Among them, the cathode catalyst paste layer includes a cathode catalyst and resin, etc. The cathode catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the cathode catalyst to the resin is, for example, 1:0.7 to 1:2. The cathode catalyst paste layer is formed, for example, by doctor blading, roll coating, or spraying.

[0071] In an embodiment of the present invention, the resins in the anode catalyst paste layer, the hydrogen consumption paste layer, and the cathode catalyst paste layer can be the same or different. Among them, the resin is, for example, selected from at least one of perfluororesin solutions (D2020), etc.

[0072] Please refer to Figure 12As described above, in an embodiment of the present utility model, when forming a membrane electrode by means of a transfer assembly, the membrane layer 100 is placed in the middle position to ensure that the membrane layer 100 is flat and free of folding. Transfer plates are provided on both sides of the membrane layer 100, for example, including a first transfer plate 131 and a second transfer plate 132. The first transfer plate 131 and the second transfer plate 132 are of the same size. Openings of the same size and position are respectively provided at the centers of the first transfer plate 131 and the second transfer plate 132 to determine the transfer area, ensuring that the areas of the catalytic layer on both sides of the membrane layer 100 after transfer are the same and the areas where the catalytic layer is located are aligned. Air during the transfer process or water vapor generated by heating can be discharged from the edges of the openings. In the present application, the size of the openings is not limited and can be set according to the size of the membrane electrode to meet the preparation requirements for forming a larger membrane electrode.

[0073] Please refer to Figure 12 As described above, in an embodiment of the present utility model, positioning holes 141 are provided at the diagonal positions of the first transfer plate 131 and the second transfer plate 132, and the positions of the positioning holes 141 on the first transfer plate 131 and the second transfer plate 132 are the same. During transfer, the membrane layer 100 is placed between the first transfer plate 131 and the second transfer plate 132, and positioning members 14 are placed in the diagonal positioning holes 141. The positioning members 14 are, for example, fluorine-containing rubber parts, etc., to fix and position the membrane layer of the membrane electrode for subsequent transfer processes.

[0074] Please refer to Figure 12 As described above, in an embodiment of the present utility model, the first transfer film 15 is provided on the side of the first transfer plate 131 away from the membrane layer 100, and the slurry layer on the first transfer film 15 faces the membrane layer 100. The second transfer film 16 is provided on the side of the second transfer plate 132 away from the membrane layer 100, and the slurry layer on the second transfer film 16 faces the membrane layer 100. The positioning member 14 defines the positions of the first transfer film 15 and the second transfer film 16. Pressures are simultaneously applied to the side of the first transfer film 15 away from the membrane layer 100 and the side of the second transfer film 16 away from the membrane layer 100 at a temperature of, for example, 130°C to 180°C, a pressure of, for example, 0.5 MPa to 4 MPa, and a hot pressing time of, for example, 10 s to 600 s to transfer the slurry layer on the transfer film to the membrane layer, and the transfer film is removed to form an anode catalyst layer and a cathode catalyst layer. By providing the transfer plates and the positioning members, air in the voids in the middle region of the sheet or water vapor generated by heating can be removed during mold closing, avoiding large-area bubble defects in the catalyst region after transfer, etc., improving the quality of the membrane electrode. At the same time, the anode catalyst layer and the cathode catalyst layer are placed and aligned on both sides of the membrane layer to ensure the uniformity and stability of catalysis and extend the service life of the electrolyzed water device.

[0075] Please refer to Figure 13 and Figure 14As described above, through the transfer method of the present application, compared with the traditional electrode catalytic layer (such as Figure 14 ), an electrode catalytic layer with good surface uniformity can be obtained (such as Figure 13 ). In some embodiments, the thickness of the electrode catalytic layer of the present application can be less than or equal to 0.15 μm, for example, 0.15 - 0.08 μm.

[0076] It should be noted that in the present application, the electrode catalytic layer of the membrane electrode can be formed on the membrane layer by in-situ growth or transfer method, and the hydrogen consumption layer of the anode catalytic layer can also be formed on the membrane layer by in-situ growth or transfer method. In one embodiment, a part of the hydrogen consumption layer of the anode catalytic layer can be embedded or fused into the membrane layer.

[0077] Please refer to Figure 8 and Figure 12 As described above, in one embodiment of the present invention, after the transfer is completed, the anode catalytic layer 11 and / or the cathode catalytic layer 12 can also be subjected to catalyst pore-forming treatment, for example, using the cold and hot cycle pore-forming method for pore-forming treatment. Specifically, in a negative pressure environment, the membrane electrode is immersed in water. After the membrane electrode is fully swollen, the temperature of the membrane electrode is slowly decreased, for example, decreased to -50 °C, and after keeping warm for 12 h, it is then slowly heated to 70 °C, and the cycle is repeated to increase the pore distribution of the catalyst. In this embodiment, the pressure of the negative pressure environment is, for example, 80 KPa, the cooling rate is, for example, 0.5 °C / min - 3 °C / min, and the heating rate is, for example, 0.5 °C / min - 3 °C / min. The pore-forming treatment method provided by the present application is simple, convenient to operate, and after the pore-forming treatment, it can increase the pore distribution of the catalyst, increase the porosity of the catalyst, increase the electrolysis rate, and improve the electrolysis efficiency. In one embodiment, the pore size of the pores of the catalyst is, for example, 1 μm - 200 μm.

[0078] The present invention also provides an electrolytic water device, and the electrolytic water device is, for example, a proton exchange membrane electrolytic water hydrogen production device, including the membrane electrode as described above. When the above-mentioned membrane electrode is applied to the hydrogen production device, it can make the hydrogen and oxygen on the anode side react to obtain water, so as to achieve the purpose of hydrogen elimination on the anode side, improve the purity of oxygen on the anode side, and improve the safety of the electrolytic water device. At the same time, improve the quality of the membrane electrode, ensure the uniformity and stability of catalysis, and extend the service life of the electrolytic water device. It can increase the electrolysis rate, improve the electrolysis efficiency, and is beneficial to promoting the development of electrolytic water hydrogen production technology.

[0079] It should be noted that the membrane electrode of the present application can be applied to a suitable electrolytic cell, such as a proton exchange membrane (PEM) electrolytic cell, an anion exchange membrane (AEM), an alkaline solution electrolytic cell, a solid oxide (SOEC), or other electrolytic cells.

[0080] In summary, the present utility model provides a membrane electrode and a hydrogen production electrolytic cell. By respectively disposing an electrode catalyst layer on the first surface and the second surface of the membrane layer, the bonding force between the electrode catalyst layer and the first surface, as well as the bonding force between the electrode catalyst layer and the second surface, can be enhanced, enabling the membrane layer and the electrode catalyst layer to be tightly bonded. It is not easy for the electrode catalyst layer and the membrane layer to peel off, thereby improving the stability of the membrane electrode, increasing the utilization rate of the catalyst in the electrode catalyst layer, and enhancing the efficiency of hydrogen production by electrolyzing water. It can simultaneously improve the purity of hydrogen and oxygen generated by electrolyzing water and enhance the safety of the electrolytic water device. It can increase the number of micropores in the membrane electrode, provide abundant pores for mass transfer, increase the porosity of the catalyst, increase the electrolysis rate, and improve the electrolysis efficiency. It can improve the quality of the membrane electrode. At the same time, the anode catalyst layer and the cathode catalyst layer are arranged and aligned on both sides of the membrane layer to ensure the uniformity and stability of catalysis and extend the service life of the electrolytic water device.

[0081] The above embodiments are merely illustrative of the principles and effects of the present utility model and are not intended to limit the present utility model. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present utility model. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present utility model should still be covered by the claims of the present utility model.

Claims

1. A membrane electrode transfer assembly, characterized in that: include: The transfer plate comprises a first transfer plate and a second transfer plate, wherein the first transfer plate and the second transfer plate are respectively provided with openings to determine a transfer area, and the first transfer plate and the second transfer plate are also provided with positioning holes, and the positions of the positioning holes on the first transfer plate and the second transfer plate are the same; Positioning parts; Wherein, during the transfer, the membrane electrode film layer is placed between the first transfer plate and the second transfer plate, and a positioning piece is placed in the positioning hole to fix and position the membrane electrode film layer.

2. The membrane electrode transfer assembly according to claim 1, characterized in that: The positioning holes are arranged at diagonal positions of the first transfer plate and the second transfer plate.

3. The membrane electrode transfer assembly according to claim 1, characterized in that: The positioning piece is a fluorine-containing rubber piece.

4. The membrane electrode transfer assembly according to claim 1, characterized in that: The first transfer plate and the second transfer plate have the same size, and the openings of the same size and position are respectively arranged at the center of the first transfer plate and the second transfer plate to determine the transfer area.

5. The membrane electrode transfer assembly according to claim 1, characterized in that: It also includes a first transfer film and a second transfer film. When transferring, the first transfer film is arranged on the side of the first transfer plate away from the film layer, and the slurry layer on the first transfer film faces the film layer; the second transfer film is arranged on the side of the second transfer plate away from the film layer, and the slurry layer on the second transfer film faces the film layer.

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